Stop light switches are actuated when operating the brake whereupon a signal is released which activates the stop light. In the presence of an anti-lock brake control and/or drive-slip control, however, this signal is also supplied to the control unit of the controller where it is used during control. The presence of this signal can thus serve to activate an ABS-control or interrupt an ASR-control.
Including this signal therefore in the control is of particular interest in order to determine whether the stop light switch is functioning or disabled due to short circuit or line damage.